[alecco]

It's in the Phi-1.5 technical paper. For phi-2 they bumped the number of tokens to 1.4 T and for sure most of it is generated, like previous models.

[IanCal]

I might be missing it but I can't find where it says how the data was generated, it mostly refers back to the previous paper which started they used 3.5

I'd not be too surprised but I can't find anything in the technical report paper saying they're using 4 specifically.